1. Field of the Invention
The present invention relates to a wireless base station and terminal using a combo of different wireless systems so as to prevent mutual radio wave interference, and more particularly to a PHS wireless LAN combo in which a PHS (Personal Handyphone System) base station and a wireless LAN (Local Area Network) base station are placed together in the same case and a PHS wireless LAN terminal.
2. Description of the Related Art
Recently, in an office, for example, a PHS base station has been installed for telephones and a wireless LAN base station has been installed for data communications in order to make telephone calls and perform data communications. In such a case, it is advantageous in terms of installation place and installation cost if the PHS base station and wireless LAN base station are placed in the same case as a combo.
A PHS system and a wireless LAN system have a different frequency band of 1.9 GHz and 2.4 GHz, respectively, but it is believed that when a combo is applied where they are accommodated in the came case, they interfere with each other, decreasing communication efficiency due to influences such as higher harmonics.
To prevent such a decrease in the communication efficiency, some means needs to be employed to eliminate the mutual interference between the base stations. For example, in JP-A-H11-308159, a reproduction intermediary device for elimination of local station wraparound interference is described to which an AGC (Automatic Gain Control) time constant switch method is applied.
The prior art teaches cancellation of the local station wraparound interference, but there has not been a technique for eliminating interference in different frequency bands or in different communication methods.